Basidiome: annual, compound, up to 20 cm in diameter, comprising numerous, spathulate or fan shaped, substipitate pilei, arising from a common base and arranged in concentric rosettes. Pileus: 2-5 cm in diameter, thin, leathery, upper surface pale pinkish brown to pale brown, with paler and darker zones; margin initially white. Hymenophore: smooth or slightly ridged, very pale pinkish to greyish brown, becoming pinkish at maturity. Flesh is very tough. Hyphal system: dimitic; generative hyphae 3 - 8 μm diameter, hyaline, thin walled, with prominent clamp-connexions; skeletal hyphae 4 - 8 μm diameter, cylindrical, hyaline, very thick-walled. Spores: 4.5 - 6.5 x 4 - 5 μm, subglobose to ovoid, hyaline, thin-walled, smooth, amyloid. Basidia: 15 - 20 x 5 - 6 μm, clavate and four spored. No cystidia. Gloeocystidia abundant, elongate, cylindrical, often constricted, up to 145 x 3-9 μm.
Listed as priority species in Section 41 of the Natural Environment and Rural Communities Act 2006. Classed as Least Concern in GB&IoM in the provisional Red Data List of Threatened British Fungi (Evans et al., 2006).
The pinkish rosettes made up of thin, tough, erect lobs is highly distinctive. Grifola frondosa can form rosette likes fruiting bodies at the base of oak trees but it has much thicker flesh and pores on the underside.
Usually associated with Quercus (oak) or more rarely Fagus (beech).
In GB&I it is widespread in England but infrequently recorded, with only two records from Wales and a single historical record from Scotland. Of conservation concern because England hosts a large proportion of the global population.
Found in woodland and parks on the ground emerging from buried roots, close to the base of broadleaved trees usually Quercus (oak) or more rarely Fagus (beech).